The present invention relates to plumbing fittings and particularly to seals for crimp connections between fittings.
In recent years, crimp-on connections have replaced the typical solder connection in copper and other metallic plumbing systems used in homes and industrial applications. Typically, the female pipe fitting will include an annular groove into which an O-ring is positioned and a male fitting inserted through the O-ring and the annular groove subsequently crimped to provide a tight seal. When numerous such connections are made in a plumbing system, particularly in large commercial installations, not infrequently crimps are missed. Frequently, O-ring seals which have not been crimped will initially pass pressure tests but, over time, will leak if the junction is not properly crimped.
There is a need, therefore, for a system which will purposely leak at a connection which has been made but not properly crimped. There have been several attempts at solving this problems, including, for example, providing frangible bands around crimp fittings which, until crimped, remain in place but, once crimped, the typically plastic ring fractures and reveals the fact that the crimp has been made. Some attempts have been made also to provide specialized O-ring designs which purposely allow leakage until such time as a proper crimp has been made.